drivers/s390/block/dasd_diag.c

   1 /*
   2  * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
   3  * Based on.......: linux/drivers/s390/block/mdisk.c
   4  * ...............: by Hartmunt Penner <hpenner@de.ibm.com>
   5  * Bugreports.to..: <Linux390@de.ibm.com>
   6  * Copyright IBM Corp. 1999, 2000
   7  *
   8  */
   9
  10 #define KMSG_COMPONENT "dasd"
  11
  12 #include <linux/kernel_stat.h>
  13 #include <linux/stddef.h>
  14 #include <linux/kernel.h>
  15 #include <linux/slab.h>
  16 #include <linux/hdreg.h>
  17 #include <linux/bio.h>
  18 #include <linux/module.h>
  19 #include <linux/init.h>
  20 #include <linux/jiffies.h>
  21
  22 #include <asm/dasd.h>
  23 #include <asm/debug.h>
  24 #include <asm/diag.h>
  25 #include <asm/ebcdic.h>
  26 #include <asm/io.h>
  27 #include <asm/irq.h>
  28 #include <asm/vtoc.h>
  29 #include <asm/diag.h>
  30
  31 #include "dasd_int.h"
  32 #include "dasd_diag.h"
  33
  34 #define PRINTK_HEADER "dasd(diag):"
  35
  36 MODULE_LICENSE("GPL");
  37
  38 /* The maximum number of blocks per request (max_blocks) is dependent on the
  39  * amount of storage that is available in the static I/O buffer for each
  40  * device. Currently each device gets 2 pages. We want to fit two requests
  41  * into the available memory so that we can immediately start the next if one
  42  * finishes. */
  43 #define DIAG_MAX_BLOCKS (((2 * PAGE_SIZE - sizeof(struct dasd_ccw_req) - \
  44                            sizeof(struct dasd_diag_req)) / \
  45                            sizeof(struct dasd_diag_bio)) / 2)
  46 #define DIAG_MAX_RETRIES        32
  47 #define DIAG_TIMEOUT            50
  48
  49 static struct dasd_discipline dasd_diag_discipline;
  50
  51 struct dasd_diag_private {
  52         struct dasd_diag_characteristics rdc_data;
  53         struct dasd_diag_rw_io iob;
  54         struct dasd_diag_init_io iib;
  55         blocknum_t pt_block;
  56         struct ccw_dev_id dev_id;
  57 };
  58
  59 struct dasd_diag_req {
  60         unsigned int block_count;
  61         struct dasd_diag_bio bio[0];
  62 };
  63
  64 static const u8 DASD_DIAG_CMS1[] = { 0xc3, 0xd4, 0xe2, 0xf1 };/* EBCDIC CMS1 */
  65
  66 /* Perform DIAG250 call with block I/O parameter list iob (input and output)
  67  * and function code cmd.
  68  * In case of an exception return 3. Otherwise return result of bitwise OR of
  69  * resulting condition code and DIAG return code. */
  70 static inline int dia250(void *iob, int cmd)
  71 {
  72         register unsigned long reg2 asm ("2") = (unsigned long) iob;
  73         typedef union {
  74                 struct dasd_diag_init_io init_io;
  75                 struct dasd_diag_rw_io rw_io;
  76         } addr_type;
  77         int rc;
  78
  79         rc = 3;
  80         diag_stat_inc(DIAG_STAT_X250);
  81         asm volatile(
  82                 "       diag    2,%2,0x250\n"
  83                 "0:     ipm     %0\n"
  84                 "       srl     %0,28\n"
  85                 "       or      %0,3\n"
  86                 "1:\n"
  87                 EX_TABLE(0b,1b)
  88                 : "+d" (rc), "=m" (*(addr_type *) iob)
  89                 : "d" (cmd), "d" (reg2), "m" (*(addr_type *) iob)
  90                 : "3", "cc");
  91         return rc;
  92 }
  93
  94 /* Initialize block I/O to DIAG device using the specified blocksize and
  95  * block offset. On success, return zero and set end_block to contain the
  96  * number of blocks on the device minus the specified offset. Return non-zero
  97  * otherwise. */
  98 static inline int
  99 mdsk_init_io(struct dasd_device *device, unsigned int blocksize,
 100              blocknum_t offset, blocknum_t *end_block)
 101 {
 102         struct dasd_diag_private *private = device->private;
 103         struct dasd_diag_init_io *iib = &private->iib;
 104         int rc;
 105
 106         memset(iib, 0, sizeof (struct dasd_diag_init_io));
 107
 108         iib->dev_nr = private->dev_id.devno;
 109         iib->block_size = blocksize;
 110         iib->offset = offset;
 111         iib->flaga = DASD_DIAG_FLAGA_DEFAULT;
 112
 113         rc = dia250(iib, INIT_BIO);
 114
 115         if ((rc & 3) == 0 && end_block)
 116                 *end_block = iib->end_block;
 117
 118         return rc;
 119 }
 120
 121 /* Remove block I/O environment for device. Return zero on success, non-zero
 122  * otherwise. */
 123 static inline int
 124 mdsk_term_io(struct dasd_device * device)
 125 {
 126         struct dasd_diag_private *private = device->private;
 127         struct dasd_diag_init_io *iib = &private->iib;
 128         int rc;
 129
 130         memset(iib, 0, sizeof (struct dasd_diag_init_io));
 131         iib->dev_nr = private->dev_id.devno;
 132         rc = dia250(iib, TERM_BIO);
 133         return rc;
 134 }
 135
 136 /* Error recovery for failed DIAG requests - try to reestablish the DIAG
 137  * environment. */
 138 static void
 139 dasd_diag_erp(struct dasd_device *device)
 140 {
 141         int rc;
 142
 143         mdsk_term_io(device);
 144         rc = mdsk_init_io(device, device->block->bp_block, 0, NULL);
 145         if (rc == 4) {
 146                 if (!(test_and_set_bit(DASD_FLAG_DEVICE_RO, &device->flags)))
 147                         pr_warn("%s: The access mode of a DIAG device changed to read-only\n",
 148                                 dev_name(&device->cdev->dev));
 149                 rc = 0;
 150         }
 151         if (rc)
 152                 pr_warn("%s: DIAG ERP failed with rc=%d\n",
 153                         dev_name(&device->cdev->dev), rc);
 154 }
 155
 156 /* Start a given request at the device. Return zero on success, non-zero
 157  * otherwise. */
 158 static int
 159 dasd_start_diag(struct dasd_ccw_req * cqr)
 160 {
 161         struct dasd_device *device;
 162         struct dasd_diag_private *private;
 163         struct dasd_diag_req *dreq;
 164         int rc;
 165
 166         device = cqr->startdev;
 167         if (cqr->retries < 0) {
 168                 DBF_DEV_EVENT(DBF_ERR, device, "DIAG start_IO: request %p "
 169                             "- no retry left)", cqr);
 170                 cqr->status = DASD_CQR_ERROR;
 171                 return -EIO;
 172         }
 173         private = device->private;
 174         dreq = cqr->data;
 175
 176         private->iob.dev_nr = private->dev_id.devno;
 177         private->iob.key = 0;
 178         private->iob.flags = DASD_DIAG_RWFLAG_ASYNC;
 179         private->iob.block_count = dreq->block_count;
 180         private->iob.interrupt_params = (addr_t) cqr;
 181         private->iob.bio_list = dreq->bio;
 182         private->iob.flaga = DASD_DIAG_FLAGA_DEFAULT;
 183
 184         cqr->startclk = get_tod_clock();
 185         cqr->starttime = jiffies;
 186         cqr->retries--;
 187
 188         rc = dia250(&private->iob, RW_BIO);
 189         switch (rc) {
 190         case 0: /* Synchronous I/O finished successfully */
 191                 cqr->stopclk = get_tod_clock();
 192                 cqr->status = DASD_CQR_SUCCESS;
 193                 /* Indicate to calling function that only a dasd_schedule_bh()
 194                    and no timer is needed */
 195                 rc = -EACCES;
 196                 break;
 197         case 8: /* Asynchronous I/O was started */
 198                 cqr->status = DASD_CQR_IN_IO;
 199                 rc = 0;
 200                 break;
 201         default: /* Error condition */
 202                 cqr->status = DASD_CQR_QUEUED;
 203                 DBF_DEV_EVENT(DBF_WARNING, device, "dia250 returned rc=%d", rc);
 204                 dasd_diag_erp(device);
 205                 rc = -EIO;
 206                 break;
 207         }
 208         cqr->intrc = rc;
 209         return rc;
 210 }
 211
 212 /* Terminate given request at the device. */
 213 static int
 214 dasd_diag_term_IO(struct dasd_ccw_req * cqr)
 215 {
 216         struct dasd_device *device;
 217
 218         device = cqr->startdev;
 219         mdsk_term_io(device);
 220         mdsk_init_io(device, device->block->bp_block, 0, NULL);
 221         cqr->status = DASD_CQR_CLEAR_PENDING;
 222         cqr->stopclk = get_tod_clock();
 223         dasd_schedule_device_bh(device);
 224         return 0;
 225 }
 226
 227 /* Handle external interruption. */
 228 static void dasd_ext_handler(struct ext_code ext_code,
 229                              unsigned int param32, unsigned long param64)
 230 {
 231         struct dasd_ccw_req *cqr, *next;
 232         struct dasd_device *device;
 233         unsigned long long expires;
 234         unsigned long flags;
 235         addr_t ip;
 236         int rc;
 237
 238         switch (ext_code.subcode >> 8) {
 239         case DASD_DIAG_CODE_31BIT:
 240                 ip = (addr_t) param32;
 241                 break;
 242         case DASD_DIAG_CODE_64BIT:
 243                 ip = (addr_t) param64;
 244                 break;
 245         default:
 246                 return;
 247         }
 248         inc_irq_stat(IRQEXT_DSD);
 249         if (!ip) {              /* no intparm: unsolicited interrupt */
 250                 DBF_EVENT(DBF_NOTICE, "%s", "caught unsolicited "
 251                               "interrupt");
 252                 return;
 253         }
 254         cqr = (struct dasd_ccw_req *) ip;
 255         device = (struct dasd_device *) cqr->startdev;
 256         if (strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) {
 257                 DBF_DEV_EVENT(DBF_WARNING, device,
 258                             " magic number of dasd_ccw_req 0x%08X doesn't"
 259                             " match discipline 0x%08X",
 260                             cqr->magic, *(int *) (&device->discipline->name));
 261                 return;
 262         }
 263
 264         /* get irq lock to modify request queue */
 265         spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
 266
 267         /* Check for a pending clear operation */
 268         if (cqr->status == DASD_CQR_CLEAR_PENDING) {
 269                 cqr->status = DASD_CQR_CLEARED;
 270                 dasd_device_clear_timer(device);
 271                 dasd_schedule_device_bh(device);
 272                 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
 273                 return;
 274         }
 275
 276         cqr->stopclk = get_tod_clock();
 277
 278         expires = 0;
 279         if ((ext_code.subcode & 0xff) == 0) {
 280                 cqr->status = DASD_CQR_SUCCESS;
 281                 /* Start first request on queue if possible -> fast_io. */
 282                 if (!list_empty(&device->ccw_queue)) {
 283                         next = list_entry(device->ccw_queue.next,
 284                                           struct dasd_ccw_req, devlist);
 285                         if (next->status == DASD_CQR_QUEUED) {
 286                                 rc = dasd_start_diag(next);
 287                                 if (rc == 0)
 288                                         expires = next->expires;
 289                         }
 290                 }
 291         } else {
 292                 cqr->status = DASD_CQR_QUEUED;
 293                 DBF_DEV_EVENT(DBF_DEBUG, device, "interrupt status for "
 294                               "request %p was %d (%d retries left)", cqr,
 295                               ext_code.subcode & 0xff, cqr->retries);
 296                 dasd_diag_erp(device);
 297         }
 298
 299         if (expires != 0)
 300                 dasd_device_set_timer(device, expires);
 301         else
 302                 dasd_device_clear_timer(device);
 303         dasd_schedule_device_bh(device);
 304
 305         spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
 306 }
 307
 308 /* Check whether device can be controlled by DIAG discipline. Return zero on
 309  * success, non-zero otherwise. */
 310 static int
 311 dasd_diag_check_device(struct dasd_device *device)
 312 {
 313         struct dasd_diag_private *private = device->private;
 314         struct dasd_diag_characteristics *rdc_data;
 315         struct vtoc_cms_label *label;
 316         struct dasd_block *block;
 317         struct dasd_diag_bio bio;
 318         unsigned int sb, bsize;
 319         blocknum_t end_block;
 320         int rc;
 321
 322         if (private == NULL) {
 323                 private = kzalloc(sizeof(*private), GFP_KERNEL);
 324                 if (private == NULL) {
 325                         DBF_DEV_EVENT(DBF_WARNING, device, "%s",
 326                                 "Allocating memory for private DASD data "
 327                                       "failed\n");
 328                         return -ENOMEM;
 329                 }
 330                 ccw_device_get_id(device->cdev, &private->dev_id);
 331                 device->private = private;
 332         }
 333         block = dasd_alloc_block();
 334         if (IS_ERR(block)) {
 335                 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
 336                             "could not allocate dasd block structure");
 337                 device->private = NULL;
 338                 kfree(private);
 339                 return PTR_ERR(block);
 340         }
 341         device->block = block;
 342         block->base = device;
 343
 344         /* Read Device Characteristics */
 345         rdc_data = &private->rdc_data;
 346         rdc_data->dev_nr = private->dev_id.devno;
 347         rdc_data->rdc_len = sizeof (struct dasd_diag_characteristics);
 348
 349         rc = diag210((struct diag210 *) rdc_data);
 350         if (rc) {
 351                 DBF_DEV_EVENT(DBF_WARNING, device, "failed to retrieve device "
 352                             "information (rc=%d)", rc);
 353                 rc = -EOPNOTSUPP;
 354                 goto out;
 355         }
 356
 357         device->default_expires = DIAG_TIMEOUT;
 358         device->default_retries = DIAG_MAX_RETRIES;
 359
 360         /* Figure out position of label block */
 361         switch (private->rdc_data.vdev_class) {
 362         case DEV_CLASS_FBA:
 363                 private->pt_block = 1;
 364                 break;
 365         case DEV_CLASS_ECKD:
 366                 private->pt_block = 2;
 367                 break;
 368         default:
 369                 pr_warn("%s: Device type %d is not supported in DIAG mode\n",
 370                         dev_name(&device->cdev->dev),
 371                         private->rdc_data.vdev_class);
 372                 rc = -EOPNOTSUPP;
 373                 goto out;
 374         }
 375
 376         DBF_DEV_EVENT(DBF_INFO, device,
 377                       "%04X: %04X on real %04X/%02X",
 378                       rdc_data->dev_nr,
 379                       rdc_data->vdev_type,
 380                       rdc_data->rdev_type, rdc_data->rdev_model);
 381
 382         /* terminate all outstanding operations */
 383         mdsk_term_io(device);
 384
 385         /* figure out blocksize of device */
 386         label = (struct vtoc_cms_label *) get_zeroed_page(GFP_KERNEL);
 387         if (label == NULL)  {
 388                 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
 389                             "No memory to allocate initialization request");
 390                 rc = -ENOMEM;
 391                 goto out;
 392         }
 393         rc = 0;
 394         end_block = 0;
 395         /* try all sizes - needed for ECKD devices */
 396         for (bsize = 512; bsize <= PAGE_SIZE; bsize <<= 1) {
 397                 mdsk_init_io(device, bsize, 0, &end_block);
 398                 memset(&bio, 0, sizeof (struct dasd_diag_bio));
 399                 bio.type = MDSK_READ_REQ;
 400                 bio.block_number = private->pt_block + 1;
 401                 bio.buffer = label;
 402                 memset(&private->iob, 0, sizeof (struct dasd_diag_rw_io));
 403                 private->iob.dev_nr = rdc_data->dev_nr;
 404                 private->iob.key = 0;
 405                 private->iob.flags = 0; /* do synchronous io */
 406                 private->iob.block_count = 1;
 407                 private->iob.interrupt_params = 0;
 408                 private->iob.bio_list = &bio;
 409                 private->iob.flaga = DASD_DIAG_FLAGA_DEFAULT;
 410                 rc = dia250(&private->iob, RW_BIO);
 411                 if (rc == 3) {
 412                         pr_warn("%s: A 64-bit DIAG call failed\n",
 413                                 dev_name(&device->cdev->dev));
 414                         rc = -EOPNOTSUPP;
 415                         goto out_label;
 416                 }
 417                 mdsk_term_io(device);
 418                 if (rc == 0)
 419                         break;
 420         }
 421         if (bsize > PAGE_SIZE) {
 422                 pr_warn("%s: Accessing the DASD failed because of an incorrect format (rc=%d)\n",
 423                         dev_name(&device->cdev->dev), rc);
 424                 rc = -EIO;
 425                 goto out_label;
 426         }
 427         /* check for label block */
 428         if (memcmp(label->label_id, DASD_DIAG_CMS1,
 429                   sizeof(DASD_DIAG_CMS1)) == 0) {
 430                 /* get formatted blocksize from label block */
 431                 bsize = (unsigned int) label->block_size;
 432                 block->blocks = (unsigned long) label->block_count;
 433         } else
 434                 block->blocks = end_block;
 435         block->bp_block = bsize;
 436         block->s2b_shift = 0;   /* bits to shift 512 to get a block */
 437         for (sb = 512; sb < bsize; sb = sb << 1)
 438                 block->s2b_shift++;
 439         rc = mdsk_init_io(device, block->bp_block, 0, NULL);
 440         if (rc && (rc != 4)) {
 441                 pr_warn("%s: DIAG initialization failed with rc=%d\n",
 442                         dev_name(&device->cdev->dev), rc);
 443                 rc = -EIO;
 444         } else {
 445                 if (rc == 4)
 446                         set_bit(DASD_FLAG_DEVICE_RO, &device->flags);
 447                 pr_info("%s: New DASD with %ld byte/block, total size %ld "
 448                         "KB%s\n", dev_name(&device->cdev->dev),
 449                         (unsigned long) block->bp_block,
 450                         (unsigned long) (block->blocks <<
 451                                          block->s2b_shift) >> 1,
 452                         (rc == 4) ? ", read-only device" : "");
 453                 rc = 0;
 454         }
 455 out_label:
 456         free_page((long) label);
 457 out:
 458         if (rc) {
 459                 device->block = NULL;
 460                 dasd_free_block(block);
 461                 device->private = NULL;
 462                 kfree(private);
 463         }
 464         return rc;
 465 }
 466
 467 /* Fill in virtual disk geometry for device. Return zero on success, non-zero
 468  * otherwise. */
 469 static int
 470 dasd_diag_fill_geometry(struct dasd_block *block, struct hd_geometry *geo)
 471 {
 472         if (dasd_check_blocksize(block->bp_block) != 0)
 473                 return -EINVAL;
 474         geo->cylinders = (block->blocks << block->s2b_shift) >> 10;
 475         geo->heads = 16;
 476         geo->sectors = 128 >> block->s2b_shift;
 477         return 0;
 478 }
 479
 480 static dasd_erp_fn_t
 481 dasd_diag_erp_action(struct dasd_ccw_req * cqr)
 482 {
 483         return dasd_default_erp_action;
 484 }
 485
 486 static dasd_erp_fn_t
 487 dasd_diag_erp_postaction(struct dasd_ccw_req * cqr)
 488 {
 489         return dasd_default_erp_postaction;
 490 }
 491
 492 /* Create DASD request from block device request. Return pointer to new
 493  * request on success, ERR_PTR otherwise. */
 494 static struct dasd_ccw_req *dasd_diag_build_cp(struct dasd_device *memdev,
 495                                                struct dasd_block *block,
 496                                                struct request *req)
 497 {
 498         struct dasd_ccw_req *cqr;
 499         struct dasd_diag_req *dreq;
 500         struct dasd_diag_bio *dbio;
 501         struct req_iterator iter;
 502         struct bio_vec bv;
 503         char *dst;
 504         unsigned int count, datasize;
 505         sector_t recid, first_rec, last_rec;
 506         unsigned int blksize, off;
 507         unsigned char rw_cmd;
 508
 509         if (rq_data_dir(req) == READ)
 510                 rw_cmd = MDSK_READ_REQ;
 511         else if (rq_data_dir(req) == WRITE)
 512                 rw_cmd = MDSK_WRITE_REQ;
 513         else
 514                 return ERR_PTR(-EINVAL);
 515         blksize = block->bp_block;
 516         /* Calculate record id of first and last block. */
 517         first_rec = blk_rq_pos(req) >> block->s2b_shift;
 518         last_rec =
 519                 (blk_rq_pos(req) + blk_rq_sectors(req) - 1) >> block->s2b_shift;
 520         /* Check struct bio and count the number of blocks for the request. */
 521         count = 0;
 522         rq_for_each_segment(bv, req, iter) {
 523                 if (bv.bv_len & (blksize - 1))
 524                         /* Fba can only do full blocks. */
 525                         return ERR_PTR(-EINVAL);
 526                 count += bv.bv_len >> (block->s2b_shift + 9);
 527         }
 528         /* Paranoia. */
 529         if (count != last_rec - first_rec + 1)
 530                 return ERR_PTR(-EINVAL);
 531         /* Build the request */
 532         datasize = sizeof(struct dasd_diag_req) +
 533                 count*sizeof(struct dasd_diag_bio);
 534         cqr = dasd_smalloc_request(DASD_DIAG_MAGIC, 0, datasize, memdev);
 535         if (IS_ERR(cqr))
 536                 return cqr;
 537
 538         dreq = (struct dasd_diag_req *) cqr->data;
 539         dreq->block_count = count;
 540         dbio = dreq->bio;
 541         recid = first_rec;
 542         rq_for_each_segment(bv, req, iter) {
 543                 dst = page_address(bv.bv_page) + bv.bv_offset;
 544                 for (off = 0; off < bv.bv_len; off += blksize) {
 545                         memset(dbio, 0, sizeof (struct dasd_diag_bio));
 546                         dbio->type = rw_cmd;
 547                         dbio->block_number = recid + 1;
 548                         dbio->buffer = dst;
 549                         dbio++;
 550                         dst += blksize;
 551                         recid++;
 552                 }
 553         }
 554         cqr->retries = memdev->default_retries;
 555         cqr->buildclk = get_tod_clock();
 556         if (blk_noretry_request(req) ||
 557             block->base->features & DASD_FEATURE_FAILFAST)
 558                 set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags);
 559         cqr->startdev = memdev;
 560         cqr->memdev = memdev;
 561         cqr->block = block;
 562         cqr->expires = memdev->default_expires * HZ;
 563         cqr->status = DASD_CQR_FILLED;
 564         return cqr;
 565 }
 566
 567 /* Release DASD request. Return non-zero if request was successful, zero
 568  * otherwise. */
 569 static int
 570 dasd_diag_free_cp(struct dasd_ccw_req *cqr, struct request *req)
 571 {
 572         int status;
 573
 574         status = cqr->status == DASD_CQR_DONE;
 575         dasd_sfree_request(cqr, cqr->memdev);
 576         return status;
 577 }
 578
 579 static void dasd_diag_handle_terminated_request(struct dasd_ccw_req *cqr)
 580 {
 581         if (cqr->retries < 0)
 582                 cqr->status = DASD_CQR_FAILED;
 583         else
 584                 cqr->status = DASD_CQR_FILLED;
 585 };
 586
 587 /* Fill in IOCTL data for device. */
 588 static int
 589 dasd_diag_fill_info(struct dasd_device * device,
 590                     struct dasd_information2_t * info)
 591 {
 592         struct dasd_diag_private *private = device->private;
 593
 594         info->label_block = (unsigned int) private->pt_block;
 595         info->FBA_layout = 1;
 596         info->format = DASD_FORMAT_LDL;
 597         info->characteristics_size = sizeof(private->rdc_data);
 598         memcpy(info->characteristics, &private->rdc_data,
 599                sizeof(private->rdc_data));
 600         info->confdata_size = 0;
 601         return 0;
 602 }
 603
 604 static void
 605 dasd_diag_dump_sense(struct dasd_device *device, struct dasd_ccw_req * req,
 606                      struct irb *stat)
 607 {
 608         DBF_DEV_EVENT(DBF_WARNING, device, "%s",
 609                     "dump sense not available for DIAG data");
 610 }
 611
 612 static struct dasd_discipline dasd_diag_discipline = {
 613         .owner = THIS_MODULE,
 614         .name = "DIAG",
 615         .ebcname = "DIAG",
 616         .max_blocks = DIAG_MAX_BLOCKS,
 617         .check_device = dasd_diag_check_device,
 618         .verify_path = dasd_generic_verify_path,
 619         .fill_geometry = dasd_diag_fill_geometry,
 620         .start_IO = dasd_start_diag,
 621         .term_IO = dasd_diag_term_IO,
 622         .handle_terminated_request = dasd_diag_handle_terminated_request,
 623         .erp_action = dasd_diag_erp_action,
 624         .erp_postaction = dasd_diag_erp_postaction,
 625         .build_cp = dasd_diag_build_cp,
 626         .free_cp = dasd_diag_free_cp,
 627         .dump_sense = dasd_diag_dump_sense,
 628         .fill_info = dasd_diag_fill_info,
 629 };
 630
 631 static int __init
 632 dasd_diag_init(void)
 633 {
 634         if (!MACHINE_IS_VM) {
 635                 pr_info("Discipline %s cannot be used without z/VM\n",
 636                         dasd_diag_discipline.name);
 637                 return -ENODEV;
 638         }
 639         ASCEBC(dasd_diag_discipline.ebcname, 4);
 640
 641         irq_subclass_register(IRQ_SUBCLASS_SERVICE_SIGNAL);
 642         register_external_irq(EXT_IRQ_CP_SERVICE, dasd_ext_handler);
 643         dasd_diag_discipline_pointer = &dasd_diag_discipline;
 644         return 0;
 645 }
 646
 647 static void __exit
 648 dasd_diag_cleanup(void)
 649 {
 650         unregister_external_irq(EXT_IRQ_CP_SERVICE, dasd_ext_handler);
 651         irq_subclass_unregister(IRQ_SUBCLASS_SERVICE_SIGNAL);
 652         dasd_diag_discipline_pointer = NULL;
 653 }
 654
 655 module_init(dasd_diag_init);
 656 module_exit(dasd_diag_cleanup);